PREFACE

From the wide range of the field of activity on 'Peat in Horticulture' not only valuable findings were lectured on, but at the same time new problems were also found, which will have to be solved. This fact led to the continuation of parallel investigations carried out in several countries. Thus an essential function of the symposium - i.e. to emphasize the scientific cooperation - has been fulfilled.

The symposium was organized and presided over by Dr. F. Penningsfeld (Weihenstephan, DBR) and Dr. D. Wille (Ghent/Belgium). Like the one held in 1966 in Helsinki, it was conspicuous by its good organization, harmonious course and generous hospitality. The gratitude for the latter should especially be rendered to the 'Torfstreuverband Oldenburg' as well as to the 'Bayer. Berg-, Hütten- und Salzwerke Rosenheim'. The sincere understanding between all of the participants may be the basis for further cooperation. As the extent of the scientific work and the concern in the findings is very high, according to a decision of those present in Bad Zwischenahn the next symposium on 'Peat in Horticulture' is to be held in 1971 in Dublin, Ireland. For this an official invitation has already been submitted by the Agriculturel Institute Kinsealy.

The ISHS welcomes the activity of the working group 'Peat in Horticulture' and wishes a lasting success. May the papers of this number of Acta Horticulturae not only again demonstrate the progress of the scientific work on peat problems, but also stimulate horticultural production.

D. Fritz
Chairman of the Section for Vegetables

Freising-Weihenstephan, February 1970


INTRODUCTION

On the occasion of the International Horticultural Congress at Brussels in 1962, the working group 'Peat in Horticulture' was initiated by members of the ISHS, as the increasing significance of research in this field was already then becoming evident. In 1966 the first symposium took place at Helsinki and was reported on in the periodical no. eight of Acta Horticulturae. In the following chapters, a compilation of lectures held during the second symposium at Bad Zwischenahn, DBR, in 1969 is made. For economic reasons it was not possible to include all lectures. The selection of reports is limited to own research work or its results.

The aim of this work was on the one hand to mark the properties of different types of peat, bogs and peatculture substrates, on the other hand to clarify the relations between the discovered properties and the success of cultivation, this being primarily the case with reference to ornamental plants and vegetables. Furthermore, questions on standardization and quality control were discussed, which play an important role in cultivation on a large scale.

While in the mornings lectures were held in the "House at the Sea", Bad Zwischenahn, three smaller excursions were arranged in the afternoons to Esterweger Dose, one of the largest bogs in Northern Germany, to the bog cultivation at Ramsloh, where peat production and processing was demonstrated, and to Sedelsberg, where the production of peatculture substrate was shown. The mechanization of peat production and the exact addition of lime and nutrient quantities to the peatculture substrate by means of electronic regulation attracted close interest. A visit to the Wiesmoor nursery, the ornamental plant nursery Klusmann at Westerstede, as well as the Rhododendronpark - then in full bloom - at Linswege, excellently rounded off the arranged courses.

On the fourth day the cultivation of exhausted bog areas and a typical treenursery on this land, which for the first time had come under the plough, was viewed. Professor Baden of the National Bog Research Institute at Bremen explained the deep ploughing method developed there, whereby the exhausted bogs are being ploughed as deeply as five to seven feet (sand-mixture culture). This day's excursion ended with a walk through the Rhododendronpark of Bremen.

Immediately after these lectures an excursion to Southern Germany was arranged from June 7 to 9, during which a visit was paid to the largescale nursery R. Mayer at Bamberg, and the experimental field of the Institute of Soil Science and Plant Nutrition at Weihenstephan. At the peat factory Raubling, situated in the Alps, a fully mechanized, largescale peat production by milling, as well as the processing and packing of peat-fertilizer-mixutres, or peatculture substrate (Plantahum) was demonstrated.

In the index, listed below, all published lectures are compiled. The introductive lectures of the first day, which were to give a general idea of the size and type of peat areas, peat cultivation methods, peat production, peat processing and peat marketing within Germany, were not included. Famous German experts lectured on these subjects.

Dr. Schneider of the State Institute of Soil Research of Lower Saxonia, Hannover, dealt with the general theme "Bogs and peat areas in Germany". With the aid of excellent survey maps he demonstrated the development, characteristics and distribution of bogs in Germany, and thus set the foundation for a better understanding of the following lectures. A display of typical peat samples in the lecture hall was of valuable help.

Chr. Koch of Ramsloh, in his lecture dealt with problems of bog drainage, applied methods of peat production in Germany and its further processing as far as huminpeat, florahum, peat-fertilizer-mixtures and peatculture substrate are concerned. In this lecture, the technical aspects and solutions, which decisively influence the profitability of peat production, as well as the quality and just prices of peat products, were strongly stressed.

In addition to this, N. Linke of the Torfstreuverband, ltd. comp., Oldenburg, spoke on "marketing of Floratorf products". At first, he set forth the development of the German peat industry during the past fifty years and explained, how its evolution was increasingly accelerated after having been comparatively slow at the beginning. Today, apart from farmers and growers, hobby gardeners and owners of a home with garden make up a large group of buyers. The trend towards the standardized quality product is a characteristic development, which has been enabled by means of peat improvement and modern packing methods.

On the second day, T. Vaage, Oslo, spoke among others on the "Jiffy⁷ Substrates and Other Substrates". These are pots moulded out of peat-culture substrate, which are sold in a highly pressed form and after their expansion are held together by a plastic net.

During the excursion to the southern area of Germany, which immediately followed the courses, Dr. Schuch of the Bavarian State Institute of Soil Culture, Plant Cultivation and Plant Protection in Munich gave a survey of Bavarian bog and peat areas and also described the specific conditions of bogformation in the Lower Alps. In reference to this, many coloured slides and a film of the Bavarian High Moor flora and fauna were preliminaries to the visit of the bogs and peat factory.

Here, once more many thanks are expressed to all lecturers, to the participating Organisations and Institutes for their decisive contribution to the success of the symposium.